CUET Level II JEE Mock Test- 1 (PHYSICS 2024-2025)

Speed of electromagnetic wave in free space is

• 1 x 10⁸ m/s

• 2 x 10⁸ m/s

• 3 x 10⁸ m/s

• 4 x 10⁸ m/s

The current in the electric circuit which arises due to flow of electrons in the connecting wires of the circuit in a defined closed path is called

• alternating current

• direct current

• conduction current

• displacement current

If a variable frequency ac source connected to a capacitor then with decrease in frequency, the displacement current will

• increase

• decrease

• remain constant

• first decrease then increase

An instantaneous displacement current of 1 A can be set up by changing the potential difference across the parallel plates capacitor (1.0 μF) at the rate of dV/dt. here dV/dt is

• 10⁶ V s^-1

• 10³ V s^-1

• 10² V s^-1

• 10¹ V s^-1

Displacement current goes through the gap between the plates of a capacitor when the charges on the capacitor

• is changing with time

• decreases

• does not change

• decreases to zero

According to Maxwell's hypothesis, a changing electric field gives rise to

• an e.m.f

• electric displacement current

• magnetic field

• pressure gradient

Displacement current is

• continuous when electric field is changing in the circuit

• continuous when magnetic field is changing in the circuit

• continuous in both types of fields

• continuous through wires and resistance only

Maxwell's modified form of Ampere's circuital law is

• ∮_s B . dl = 0

• ∮_s B . dl = μ₀I

• ∮_s B . dl = μ₀I + 1/ε₀ dq/dt

• ∮_s B . dl = μ₀I + μ₀ε₀ dΦ_E/dt

When an electromagnetic waves enter the ionised layer of ionosphere, the motion of electron cloud produces a space current and the electric field has its own capacitative displacement current, then

• the space current is in phase of displacement current

• the space current lags behind the displacement current by a phase 180⁰.

• the space current lags behind the displacement current by a phase 90⁰.

• the space current leads the displacement current by a phase 90⁰.

In order to establish an instantaneous displacement current 5 mA in the space between the plates of 5μF parallel plate capacitor, the potential difference need to apply is

• 100 Vs^-1

• 200 Vs^-1

• 300 Vs^-1

• 1000 Vs^-1